The present invention relates to a method of transferring loops using a flat knitting machine and to an apparatus for transferring the loops.
Normally, in order to expandably open a loop of a delivery-side knitting needle and to surely hook the loop with a hook of a receiving-side knitting needle, a loop expanding member is provided for any conventional knitting needle of a flat knitting machine incorporating a loop transfer function. The loop expanding member is attached to a lateral surface of the delivery-side knitting needle. The loop expanding member called "wing", enables a receiving-side knitting needle to penetrate into a clearance between a delivery-side knitting needle and said clearance (in transferring) in order that the loop of the delivery-side knitting needle can smoothly be transferred to the receiving-side knitting needle.
Generally, knitting needles provided for a flat knitting machine are classified into two kinds including the following: A "latch" needle having an end being swingably held by an aperture of a hook at the top end of each knitting needle. The aperture of this hook is opened and closed by means of a brush or knitting yarn that passes through the latch needle. The other one is called a "compound" needle whose aperture is opened and closed by means of a slider which is operated by a cam provided for a carriage unit.
While a carriage moves to the left in a flat knitting machine furnished with a number of latch needles, loci of the delivery-side knitting needles and receiving-side knitting needles in the course of transferring stitches from those knitting needles of the rear-side needle bed to those knitting needles of the front-side needle bed are typically illustrated in FIG. 1. On the other hand, FIG. 2 illustrates loci of the delivery-side knitting needles and the receiving-side knitting needles of a flat knitting machine furnished with compound needles.
Nevertheless, on the way of transferring stitches with a flat knitting machine furnished with latch needles, stitches held with those delivery-side knitting needles are apt to be slidably moved along the delivery-side knitting needles accompanying the forward movement of these knitting needles. In consequence, loops may not be properly guided to the predetermined delivery position of those delivery side knitting needles.
If loops were not properly guided, then loops cannot correctly be engaged with hooks of corresponding receiving-side knitting needles. If these loops were cleared from those delivery-side knitting needles, then all stitches will be constricted. To prevent this, those ascended delivery-side knitting needles are retracted in order to release tension between those knitting needles and stitches, and then, those delivery-side knitting needles are again set to the stitch delivery position before permitting those receiving-side knitting needles to move on themselves until reaching the loop receiving position so that loops can eventually be transferred to these receiving-side knitting needles.
In this case, those receiving-side and delivery-side knitting needles respectively start to intersect with each other at position X shown in FIG. 1. Therefore, the above cited conventional flat knitting machine needs to provide each delivery-side knitting needle with such a cam mount for releasing tension between the delivery-side knitting needle and stitch and another cam mount for again guiding those delivery-side knitting needles to the loop transferring position, thus requiring provision of a lock having an expanded width. In other words, the flat knitting machine needs to install a large-dimensional carriage.
Furthermore, since loops are forcibly lifted while knitting needles move forward, an unwanted load is applied to stitches to cause the knitting yarn to easily be cut off. In consequence, when composing a knit with those knitting yarns containing poor elasticity or by closely putting stitches together, independent of the forward and backward movements of knitting needles, any conventional flat knitting machine cannot securely prevent loops from being lifted forcibly.
The Japanese Patent Publication No. 1-37495 of 1989 proposes such a flat knitting machine furnished with compound needles. Nevertheless, as is clear from loci shown in FIG. 2, the installed lock is not provided with a pair of cam mounts essential for materializing those loci X1 and X2 shown in FIG. 1, which are necessary for the system to fully prevent loops from forcibly being lifted. In consequence, like the flat knitting machine furnished with latch needles cited above, loops engaged with those delivery-side knitting needles may also be lifted relative to the forward movement of the delivery-side knitting needles, thus preventing loops from properly being transferred to the receiving-side knitting needles.
Therefore, the invention has been achieved to fully solve those technical problems inherent in any of those conventional flat knitting machines. An object of the invention is to provide a novel method of and a novel apparatus for securely guiding stitches to the predetermined transferring position without incurring load to stitches on the way of a transfer operation. Characteristically, the novel method embodied by the invention enables anyone concerned to easily design and manufacture compact carriages.